Twenty years of transcriptomics, 17alpha-ethinylestradiol, and fish

Area of Science:

• Aquatic toxicology and environmental science.
• Comparative endocrinology and endocrine disruption research.
• Genomics and transcriptomics in fish.

Background:

• 17alpha-ethinylestradiol (EE2), a component of birth control pills, is a potent environmental estrogen.
• Omics technologies have advanced the study of EE2's effects on aquatic organisms, particularly fish.
• Vitellogenin has emerged as a critical biomarker for estrogenic exposure in fish.

Purpose of the Study:

• To review the current understanding of estrogen receptor signaling in fish exposed to EE2.
• To identify knowledge gaps in tissue-specific responses to EE2.
• To outline future directions for omics-based research on endocrine disruption in aquatic environments.

Main Methods:

• Analysis of transcriptome responses to EE2 across various fish species.
• Review of approximately 40 studies investigating EE2's impact on gene expression.
• Identification of altered transcriptional networks in liver and testis tissues.

Main Results:

• EE2 significantly alters gene expression in fish, with vitellogenin as a primary indicator.
• EE2 treatment impacts liver networks involved in protein synthesis (increased) and xenobiotic metabolism/immune function (decreased).
• Knowledge gaps exist regarding EE2-induced transcriptional changes in non-liver/testis tissues like spleen, kidney, and pituitary.

Conclusions:

• Omics studies have significantly advanced our understanding of EE2's endocrine-disrupting effects in fish.
• Tissue-specific responses to EE2 are crucial and require further investigation.
• Future research should integrate omics data into monitoring programs, utilize computational approaches, and develop predictive models for endocrine disruption.